<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<script>
    var now = new Date();
    var dayfweek = now.getDay()
    if (dayfweek == 0) {
        alert("星期天")
    } else if (dayfweek == 0) {
        alert("星期一")
    }else if (dayfweek == 1) {
        alert("星期二")
    }else if (dayfweek == 2) {
        alert("星期三")
    }else if (dayfweek == 3) {
        alert("星期四")
    }else if (dayfweek == 4) {
        alert("星期五")
    }else {
        alert("星期六")
    }



</script>

</body>
</html>